Pigtail forming tool with slide ram



Feb. '25, 1958 I w, 5. SMITH 2,824,473

PIGTAIL FORMING TOOL WITH SLIDE RAM Filed May 3, 1956 FIG 3 INVENTOR. WJESLESI 8. SMITH BYW A1 TTaRA/Eya United States Pate PIGTAIL FORMING TOOL WITH SLIDE RAM Wesley Simon Smith, Cedar Rapids, Iowa, assignor to Collins Radio Company, Cedar Rapids, Iowa, a corporation of Iowa Application May 3,1956, Serial No. 582,441

1 Claim. (Cl. 81-15) This invention relates to hand tools and more particularly to a tool usable in the manufacture of screw adjusted tuning slugs.

Previous to this invention only very slow procedures were available for the production of tuning slugs positioned by a threaded shank. The tuning slug consists of a cylindrical mass of powdered iron with a pigtail extending axially from one end of the cylinder. The problem is to cut the pigtail to the proper length, insert it in the end-slotted, threaded. shank, and fasten the pigtail to the threaded shank to provide a mounting and adjusting means for the slug. A precise trimming of the pigtail lead and bending over of the tip of the pigtail is necessary to prevent the lead from projecting radially out of the slotted end. Soldering methods alone are not feasible since solder somehow always managed to get on the threads requiring further steps cleaning up the threaded portion.

Accordingly, it is an object of the invention to provide a tool which cuts the pigtail to the proper length, holds the assembled portion and bends over the tip of the pigtail just suificiently assemblying the device ready for tack soldering.

It is a further object of this invention to provide a hand tool which permits streamlined operator procedure in the manufacture of a tuning slug.

It is yet another object of this invention to provide a hand tool with sufiicient ease of operation to permit assembly line use by women operators.

It is a feature of this device that it enables the operator to manufacture a slug assembly with a minimum of motions yet provides precise results.

Further objects, features, and advantages of the invention will become apparent when read in conjunction with the drawing, in which;

Figure 1 shows a plan view of the tool,

Figure 2 shows a broken perspective view of the jaws in front of the hinge showing additionally two steps in the procedure in which the tool is used, and

Figure 3 shows the sequence in the manufacture of the slug assembly.

In Figure 1 the tool is shown with the jaws and 11 slightly open. Jaw 10 is an extension of handle 12 and jaw 11 is an extension of handle 13. The handles are pivoted at a point 14 which pivot point is obscured by a boss 15.

Jaws 10 and 11 terminate in thin tips 17 and 18 respectively. Adjacent said tips inwardly toward the pivot is a pair of mating surfaces 19 and 20 which comprise a cutting portion. These surfaces are set a desired dimension from the tips 17 and 18. When the handles 12 and 13 are closed together, surfaces 19 and 20 pass and in so doing perform a cutting operation on wires extending radially from the pivot. The normal to the planes 19 and 20 is substantially perpendicular to the pivot 14. The tips and the cutting surfaces are parallel to the pivot; the length of the wire pigtail cut is thus the same wherever cut in the tool. Further in toward pivot 14 from the cutting surface, on jaw 10, is a pocket 22. This pocket has sutficient size to accommodate the threaded shanks which are involved with this tool. At the bottom of pocket 22 is a lip 23 which encloses the bottom of the pocket. Opposite pocket 22 is a relief portion 24 which closes the pocket on the open side when the jaws are closed. At the'bottom of the pocket is a slot 25 which permits insertion and removal of the pigtail before and after assembly of the slug.

Boss 15 is mounted on jaw 10 and handle 12 so as.

not to interfere with the pivot 14. Inside boss 15 is, a

passageway shaped to accommodate ram 27.. This-ramhas a slot 28 at one end which receives the end of fingerlever 29. Finger lever is pivoted at point 30. This pivot is also mounted on handle 12 in a second boss 31. Between finger lever 29 and handle 12 a spring 33 is mounted engaging a small pin 34 on the finger lever and retained by a relatively short hollow cylinder 35 fixed to handle 12. The opposite end 37 of ram 27 stands at rest closely adjacent pocket 22.

In Figure 2 the jaws are shown in perspective to illustrate their arrangement and to show the use of the tool. The effective cutt'mg position of surfaces 19 and 20 is determined by the distance between these surfaces and tips 17 and 18. A slug 40a with pigtail 41a is shown in position for cutting the pigtail to length. Closure of the jaws by squeezing together handles 12 and 13 performs this cutting operation. Since tips 17 and 18, planes 19 and 20 and pivot 14 are mutually parallel, positioning of the slug 40a anywhere within the jaws with the pigtail parallel to the normal to planes 19 and 20 assures a precise cutting to length. The relieved portion 24 has sufiicient clearance adjacent the cutting portion of the opposing jaw near 19 to permit the tool to close down completely despite the tret from the clipped pigtail.

While the jaws are substantially closed, from cutting the pigtail to length, the operator takes tuning slug 40b from the cutting area of the jaws and positions it below the pocket 22 of the upper jaw 10, with the trimmed pigtail 41b projecting upwardly through slot 25 into the pocket 22. The threaded shank 42 is then inserted into the pocket 22 concentrically to the pigtail, now 410, corresponding to Figure 3c, and the jaws are closed completely. The slot 43 of the threaded portion is turned to be parallel to and in line with the path of ram end 37. Actuation of handle 29 moves ram 27 over the end of the threaded shank 42 bending over the pigtail. Figure 2 shows the downwardly-extending tong portion 38 which is shaped to enter slot 43 of shank 42 and bend over the tip of 410.

These sequences of steps are shown in Figure 3. A shows slug 40a with pigtail 41a in its original length. B shows slug 40b with pigtail 41b trimmed to length according to the distance between tip 17 and surface 19. bled thereon and slot 43 oriented to the path of the ram end 37. D shows the completed slug assembly with the tip of the pigtail 41d bent over within the slot 43 but not projecting out beyond the root diameter of the threads of shank 42.

The jaws of the tool are then opened and the assembly removed therefrom through the slot 25. Subsequent operations includetouching solder and heat to the slot 43 to fix pigtail 41a in the threaded shank with a tack of solder.

Thus, a slug assembly is manufactured which will run within a threaded mount for adjustment of the tuning slug position, with a minimum of extra steps cleaning up after the assembly operation. The position of the threaded shank relative to the cylindrical ferromagnetic material is fixed to a high degree of precision due to C shows B with the threaded shank 42 assem-' the use of the cutting surface 19 coupled with the fixed positioning of the assembly in pocket 22.

Although this invention has been described with respect to particular embodiments thereof, it is not to be so'limited because changes and modifications may be made therein which are within the full intended scope of the invention as defined in the appended claim.

A tool comprising a pair of crossed levers, a pivot joining the two levers with portions extending in one direction from the pivot: formed as handles and portions extending in the opposite direction formed as jaws, onc jaw having an open-sided pocket with the open side facing the other jaw, 21 surface of said one jaw forming a bottom wall of said pocket, said bottom wall having a slot opening toward said other jaw, ram means slidably mounted on said one jaw between the pivot and the References Cited in the file of this patent UNITED STATES PATENTS 311,121 Hair Jan. 20, 1885 345,215 Crocker July 6, 1886 456,966 Schweeters Aug. 4, 1891 651,896 Stoolfire June 19, 1900 1,381,024 Shaul June 7, 1921 

